Thus, we may see one day, two generals of alleged French Canadian extraction-Jean Charles Fremont and Pierre Toutan de Beauregard-at the head of powerful armies, one from the Northern States and the other from this Confederacy, contending with each other on the banks of the Potomac, or the Ohio, or the Mississippi, for the independence or the subjugation of this country.--N. O. Picayune, August 14.